In a cellular wireless communications system, there are typically performance degradation issues at cell boundary regions due to inter-cell interference in a dense deployment. For example, in a typical dense cellular deployment, 35% of the mobiles have close or below 0 dB SNR due to interference from adjacent cells. One approach which attempts to improve performance at the cell boundary regions is to incorporate multiple relay stations which relay signals between base stations and access terminals. The use of multiple relay stations can provide some improvement in the cell boundary regions. However, the improvement is limited due to the introduction of relay station boundary regions into the system where the inter-relay-station interference can cause performance degradation in a similar fashion to inter-cell interference.
Based on the above discussion there is a need for new methods and apparatus which can improve performance in a wireless communications system including relay stations. Methods and apparatus directed to the mitigation of interference in relay station boundary regions would be beneficial.